python基础篇- _dict_字典和列表推导式

类的_dict_属性：收集类和实例的属性和值，并返回一个字典

类的_dict_属性：内置的和自定义属性的字典

实例的_dict_属性：自定义的属性字典

 eg: new_list = [i._dict_ for i in self.student_list]

try:
    f.open('student.data')
except:
    f.open('student.data','w')
else:
    data = f.read()

    new_list = eval(data)
    self.stu_list = [Student(i['name'], i['age']) for i in new_list]
finally:
     f.close()